"""数据库引擎与会话管理"""

from pathlib import Path
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker, declarative_base

DB_PATH = Path(__file__).parent.parent.parent / "data" / "web.db"
DB_PATH.parent.mkdir(parents=True, exist_ok=True)

engine = create_engine(
    f"sqlite:///{DB_PATH}",
    connect_args={"check_same_thread": False},
    echo=False,
)

SessionLocal = sessionmaker(bind=engine, autocommit=False, autoflush=False)
Base = declarative_base()


def get_db():
    """FastAPI 依赖：提供数据库会话，请求结束自动关闭。"""
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


def init_db():
    """建表 + 写入初始数据。"""
    Base.metadata.create_all(bind=engine)
    _seed()


def _seed():
    """写入默认超管账号和角色。"""
    from .models import User
    from .security import hash_password

    db = SessionLocal()
    try:
        if not db.query(User).first():
            admin = User(
                username="admin",
                password_hash=hash_password("admin123"),
                role="super_admin",
                is_active=True,
                remark="默认超级管理员",
            )
            db.add(admin)
            db.commit()
    finally:
        db.close()